A number of methods to obtain a location of a device or user exist. These location estimation methods include methods based on global positioning system (GPS) or methods based on cellular base station signal strength. However, these systems suffer from various shortcomings. For example, GPS methods fail to work indoors where the satellite communication is not possible. The methods based on cellular base station signal lack sufficient accuracy. For example, conventional methods cannot distinguish between floors in a building, or two adjacent rooms and thus lack greater granularity in determining the location.